As someone who has used both TS3 and Vent, TS3>Vent in all ways.
99% of servers I go on have adverts for their TS3 server. Guess who that 1% that doesn't is? SG is the only server I've ever been on that has vent.
Honestly don't think it'd be that hard to make the switch over from vent. Maybe a little time consuming yes.